I need a subwoofer/sub-bass opinion from you


Hello All--

I have a large room (well large to me).  It's 20' long, 15 wide, and 10' tall.  I run either Klipsch Forte IIIs or PSB Imagine T2s through a tube amp.  I have plenty of volume with either loudspeaker.  

What I want to accomplish is to add sub bass.  I did this previously in a smaller room with a Sumiko S5 (I believe it's the same or similar to the REL T5).    When I had the Sumiko dialed in, the system congealed into a wonderful sound.  There was no noticeably appreciable sound coming from the sub.  Instead, it merely filled out the lowest octave and added space, dynamics, and really made the highs seem less harsh.  

The Sumiko S5 does help in this setup but it's just not enough to charge the room or at least add enough.  

I'm thinking REL.  Thoughts? 

PS  When I ran the Sumiko, it sounded clearly better when I ran it off the amp speaker outs than off my Primaluna's dedicated subwoofer out. 
128x128jbhiller
I've done a lot of research on subs.  Hsu Research makes a fantastic product.  Recently, I e-mailed Hsu regarding several technical questions and I received a very thorough and very professional response, as well as a recommendation that I add a high pass filter.  
I highly recommend purchasing Hsu products.  
"I highly recommend purchasing Hsu products"
Have you listened to Hsu products? I haven’t - only my existing single REL R-328, which sounds great for me.

But I’m upgrading - below are the candidates. Pricing is per sub if purchasing dual (SVS will -$100 from the 2x total). REL is not on the list: they’re over-priced compared to these competitors, of which the PSA’s are the priciest.

The HSU and PSA models use paper drivers, not aluminum. Does it matter, objectively? I don’t know.

The Rythmik and HSU models appear to support speaker-level line in. Comparable to REL’s fancy-pants Neutrik connection? Maybe.

sub | $$$ | driver | amp | freq. | size | spkr-level input?
Rythmix F12 | $893 free ship | 12" aluminum | 370w rms class A/B servo | 14-100Hz ±2dB | 15.75x15.75x17, 62lbs | yes
Rythmix F12-300 | $700 free ship | 12" aluminum | 300w rms Hypex servo amp | 14-100Hz ±3dB | 15.75x15.75x17, 57lbs | yes
SVS SB-3000 | $999 free ship | 13" aluminum | 800w rms class D | 18-270Hz ±3dB | 15.6x15.2x17.8 | 54.5lbs | no
HSU ULS-15 MKII | $779 + shipping | 15" paper | 600w rms class D | 20-200Hz, ±1dB | 18x18x18, 65lbs | yes
PSA S1510 | $1,300 | 15" paper | 960w rms class D | 19-200Hz
±3 dB | 17x17.25x18, 63lbs | ???
It will soon be 2019 and you're considering flip phone subs.

Subwoofers with room correction that are adjustable from your listening position have become affordable. 

Every subwoofer suggested here can do the job, but how easily and how well they can be integrated to your system and your room is questionable. Compare their setup procedures then look at the procedures here.
http://syzygyacoustics.com

Or here.
http://velodyneacoustics.com/pdf/digitaldriveplus/DD+Manual.pdf
"... how easily and how well they can be integrated to your system and your room is questionable"
@m-db have you listened to Syzygy subs?

Wrt flip phones the SVS SB-3000 does appear to offer from-your-butt control via Android/iOS app. At a glance the control doesn’t look as refined as Syzygy’s.

Whether those or Velodyne units and their integrated DRC systems perform at or above the levels of comparable "flip phones" should also be questionable. REL, Rythmik, SVS, HSU and PSA all still seem to be in business, developing/improving and supporting their products within constraints of those businesses, and from feedback here and elsewhere seem to have their shares of discerning owners.

Yes I’d prefer to integrate subs into my 2ch rig from the comfort and optimal location of my butt. But I wouldn’t weigh that feature inordinately above overall sonic performance, reliability/service* and fair value. For now I’m fine with some manual monkeying.

* : check recent reviews on Velodyne service and reliability, here: https://tinyurl.com/yasef699